Answer:
1,373.4 N
Explanation:
The mass of the table acts at the centre in addition to the books since that is the centre of gravity of the table.
Mass of books will be 10kg+20kg+30kg=60 kg
Total mass of table and books will be 500kg+60kg=560 kg
This mass is evenly distributed into the four legs hence 560kg/4 legs=140 kg per leg
Force is product of mass and acceleration due to gravity hence F=gm
Taking g as 9.81 m/s2 then
F=140*9.81=1,373.4 N
Therefore, rhe normal force is equivalent to 1,373.4 N
Explanation:
Bulbs are nothing but resistors that glow when current passes through them.
In Set A, the bulbs (resistors) are connected parallely to each other, this means that even if one of the bulbs fuses or removed, the circuit will still be completed and others continue to glow.
And in parallel connection if the resistance of the two resistors are same powered delivered to each is same.
In Set B, bulbs are in series connection, this means that when one of the bulb is removed or fuses, the circuit will break and other bulbs can not operate.In this situation as well if the resistance of two resistors is same then the power delivered is same.
Answer:
Lubrication is used to reduce friction. It is generally used for moving machine parts. The lubricants are the substances which are used to reduce the friction which acts between two surfaces in contact, between which relative motion can occur.
Answer:
a. Stars all warm objects
c. Some unstable atomic nuclei
Explanation:
Gamma rays are photons of very high energy (beyond 100keV) enough to remove an electron from its orbit.
They have a very short wavelength, less than 5 meters from the peak, and can be produced by nuclear decay, especially in the breasts of massive stars at the end of life.
They were discovered by the French chemist Paul Villard (1860 to 1934).
While X-rays are produced by electronic transitions in general caused by the collision of an electron with an atom at high speed, gamma rays are produced by nuclear transitions.
Gamma rays produce damage similar to those caused by X-rays or ultraviolet rays (burns, cancer and genetic mutations).
The sources of gamma rays that we observe in the universe come from <u>massive stars (hypernovas) or some warm objects on the space</u> that end their lives by a gravitational collapse that leads to the formation of a neutron star or a black hole, as well as <u>unstable radioactive nuclei </u>that emit radiation gamma to reach its steady state.
Answer:
She must be launched with minimum speed of <u>57.67 m/s</u> to clear the 520 m gap.
Step-by-step explanation:
Given:
The angle of projection of the projectile is, 
°
Range of the projectile is, 
m.
Acceleration due to gravity, 
The minimum speed to cross the gap is the initial speed of the projectile and can be determined using the formula for range of projectile.
The range of projectile is given as:
Plug in all the given values and solve for minimum speed, 
.
Therefore, she must be launched with minimum speed of 57.67 m/s to clear the 520 m gap.
